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SCIENTIFIC ADVANCES iN POLYCHAETE
RESEARCH
R. Sardá, G. San Martín, E. López, D. Martin
and D. George (eds.)
SCIENTIA MARINA 70S3
December 2006, 139-144, Barcelona (Spain)
ISSN: 0214-8358
A new species of Pista (Annelida: Polychaeta:
Terebellidae) from shallow waters of Shizugawa Bay,
Sanriku Coast, Japan.
EIJIROH NISHI 1 and KATSUHIKO TANAKA 2
1
Manazuru Marine Laboratory for Science Education, Yokohama National University, Iwa, Manazuru, Kanagawa 2590202, Japan E-mail: [email protected]
2
Shizugawa Nature Centre, Shizugawa, Miyagi 986-0781, Japan
SUMMARY: A new species of the genus Pista (Annelida: Polychaeta: Terebellidae) was found on a boulder bottom in shallow waters of of Shizugawa Bay, Sanriku coast, northern Honshu, Japan. Individuals of this species measure 5 to 10 cm long
and 3 to 5 mm wide. There are two pairs of branchiae on segments 2 and 3, each with an annulated long stalk and many
dichotomous branches. The peristomium and segment 3 have elongate, semi-circular lateral lobes, segments 2 and 4 each
have small lobes, segments 5 and 6 have very small lobes inserted between the neuropodium and ventral pad. Individuals of
the new species have 17 pairs of notopodia from segment 4 and conical nephridial papillae on segments 6 and 7. The new
Japanese species differs from all known species in the structure of the branchiae and the lateral lobes of anterior chaetigers.
Keywords: Polychaeta, Shizugawa, Tohoku, Pista, new species, Terebellidae, taxonomy.
RESUMEN: UNA NUEVA ESPECIE DE PISTA (ANNELIDA: POLYCHAETA: TEREBELLIDAE) DE AGUAS SOMERAS DE LA BAHÍA DE
SHIZUGAWA, COSTA DE SANRIKU (JAPÓN). – Una nueva especie de Pista (Annelida: Polychaeta: Terebellidae) fue encontrada
en fondos someros de cantos rodados de la Bahía de Shizugawa, Costa de Sanriku (Norte de Honshu, Japón). Los individuos
de esta nueva especie miden de 5 a 10 cm de largo y de 3 a 5 mm de ancho. Presentan 2 pares de branquias en los segmentos 2 y 3, cada uno con un largo pedúnculo anulado y ramas dicotómicas. El peristomio y el segmento 3 presentan lóbulos
laterales elongados y semicirculares, los segmentos 2 y 4 presentan lóbulos pequeños y los segmentos 5 y 6 lóbulos muy
pequeños insertados entre el neuropodio y la zona ventral. Los individuos de la nueva especie tienen 17 pares de notopodia,
desde el segmento 4, y papilas nefridiales cónicas en los segmentos 6 y 7. La nueva especie difiere de las especies conocidas en la estructura de las branquias y los lóbulos de los setígeros anteriores.
Palabras clave: Polychaeta, Shizugawa, Tohoku, Pista, nueva especie, Terebellidae, taxonomia.
INTRODUCTION
We have studied the terebellids from Shizugawa
Bay, Sanriku coast, Tohoku region, northern
Honshu, Japan (Fig. 1). We collected eight species
of the family, of which three or four species are
probably new to Japan, and one species is new to
science. We report here on the new taxon of
Terebellidae from the shallow water of Shizugawa
Bay, Japan.
Seven species of Pista have been recorded from
Japanese waters: P. atypica Hessle, 1917; P. cristata (Muller, 1776); P. elongata Moore, 1909; P. fasciata sensu Marenzeller, 1885; P. fasciata sensu
MacIntosh, 1885; P. microlobata Hessle, 1917; P.
robustiseta Caullery, 1915 (Imajima and Hartman,
1964; Uchida, 1992). These records and descriptions are brief and provide limited information on
the features distinguishing these species. A revision
of the Japanese species is required.
140 • E. NISHI and K. TANAKA
FIG. 1. – Map of Shizugawa Bay and Tohoku region (left) and map of Shizugawa Bay and collection site (Kappazawa)(right).
The genus Pista Malmgren, 1866 has been
revised by Hutchings (1977), Hutchings and Glasby
(1988) and Hutchings (1990). We have expanded
their generic diagnosis of Pista (Hutchings and
Glasby, 1988) to include species with lateral lobes
on segments 2-6 and describe a new species, and
compare this with previously described species from
Japan and the Pacific.
MATERIALS AND METHODS
Terebellid polychaetes were collected by hand
using SCUBA in depths of 10m on boulder bottoms.
The worms were collected from the underside of
stones where the tubes were attached, and were transported to the laboratory. Animals were fixed in 10%
neutralized formaldehyde and subsequently transferred to 70% ethanol. Two specimens were transferred through an ethanol series and butylalcohol,
freeze dried using a Hitachi ES-2030 Freeze Dryer,
coated with palladium by an Hitachi E-1010 Ion
Sputterer, and observed on a Hitachi SEM S-3000N
scanning electron microscope. Notochaetae and neurochaetae from the paratypes were permanently
mounted on to slides for detailed examination.
SCI. MAR., 70S3, December 2006, 139-144. ISSN: 0214-8358
Material of the new species is deposited in the
following museums:
USNM, United States National Museum,
Smithsonian Institution, Washington, DC,USA.
AHF-LACM, Allan Hancock Foundation
Polychaete Collection, Los Angeles County
Museum, California, USA.
AM, Australian Museum, Sydney, Australia
CMNH, Coastal Branch of the Natural History
Museum and Institute, Chiba, Katsuura, Chiba
Prefecture, Japan
NHM, The Natural History Museum, London, UK
SAM, South Australian Museum, Adelaide,
Australia
SMF, Senckenberg Museum, Frankfurt,
Germany
ZMUC Zoological Museum, University of
Copenhagen, Copenhagen, Denmark.
SYSTEMATICS
Genus Pista Malmgren,1866 emended
Diagnosis. Lateral lobes on segments 2-4 or 2-6;
and sometimes on peristomium. Branchiae 1-3
NEW SPECIES OF PISTA (TEREBELLIDAE) FROM JAPAN • 141
pairs. Other characters are the same as in the
Hutchings and Glasby (1988)definition.
Remarks. We have expanded the generic diagnosis of Pista to include species with lateral lobes on
segments 2-6. Previously, the genus was regarded as
having lateral lobes on segments 2-4 (Hutchings,
1977; Hutchings and Glasby, 1988). Hutchings and
Glasby (1988) suggested that several groups exist in
the genus. The species having lateral lobes on segments 2-6 reported herein belongs to a group previously unknown. Except for the distribution of lateral lobes of anterior chaetigers, however, other features of this species indicate that it belongs to the
genus Pista.
Pista shizugawaensis n. sp.
(Figs 2-4)
Material examined. Holotype – CMNH-ZW01800 Kappazawa,
Shizugawa Bay, Miyagi, Japan, collected by K. Tanaka, 14 August,
2003. Paratypes, collection site and collector are the same as for the
holotype:AM-W29405, 14 Aug 2003, SMF 15178, 11 June 2003;
NHM-2005.1516, 14 August, 2003; USNM-1078490, 7 May, 2003;
SAM-E3457, 14 August, 2003; ZMUC-POL-1851, 11 June 2003;
LACM-AHF-POLY 2170, 7 May, 2003. Non-type material, collection site and collector are the same as for the holotype: CMNHZW01798, on SEM stub.
Description. Preserved body brown to pale
brown, in life light brown to light yellow. Body
length 50 to 150 mm, thoracic width 1.5 to 4.0 mm,
abdominal width 0.5 to 2.0 mm. Buccal tentacles
numerous, arising from thickened glandular margin
(Figs 2A, 4A). Prostomium compact with anteriorly
projecting “tongue”, glandular with convoluted margins. Eye spots absent. Peristomium thickened, with
large lateral semi-circular lobes connected by a Ushaped thickened ridge (Fig. 2A, B, C).
Branchiae 2 pairs on segments 2 and 3, each pair
consisting of equal- (NHM-2005.1516) or unequalsized branchiae (ZMUC-POL 1851), largest on segment 2 and smallest on segment 3 (SMF-15178) or
largest on segment 3 and smallest on segment 2
(SAM E3457) (Fig. 2A). Branchial stalk stout with
FIG. 2. – Anterior part of Pista shizugawaensis n. sp. (SAM E3457). A, dorso-lateral view. B, ventral view. C, ventro-lateral view. b,
branchia. llo, lateral lobe. np, nephridial papillae. p, peristomium. Scale is 1 mm.
SCI. MAR., 70S3, December 2006, 139-144. ISSN: 0214-8358
142 • E. NISHI and K. TANAKA
FIG. 3. – Branchia, notochaetae and uncini of Pista shizugawaensis n. sp. A and B are from paratype AMS-W29405, A, dorsal view of
branchiae from chaetiger 2. B, dorsal view of branchiae from chaetiger 3. C, small-sized, 3rd left branchia from holotype. D, small-sized, 2nd
left branchia from SAM E3457. E, F, chaetae from chaetiger 6. G–K, thoracic uncini, drawn from SEM photos. G, K, 2nd chaetiger. H,
6th chaetiger. I,J, 16th chaetiger. L, abdominal uncini. Scale 1 mm in A-D, 50 μm in E-J, 30 μm in L, 25 μm in K.
marked annulations, plume-shaped with a tuft of
branched filaments that arise from the main stalk
irregularly spirally(Figs. 2A, 3A-D, 4A, B).
Lateral lobes present on segments 2, 3, 4, 5 and 6:
segment 2 with ventro-lateral lobes, fused midventrally; segment 3 with wide, semi-circular lateral
lobes, discrete and not continuing dorsally or ventrally; segment 4 with small narrow lateral lobes which
continues to ventral pad; and segments 5 and 6 with
very small narrow lateral lobes, ventrally arranged,
located between neuropodial uncinal row and ventral
pad (Fig. 2B, C). Ventral pads conspicuous on thoracic chaetigers. Noticeable spherical nephridial
SCI. MAR., 70S3, December 2006, 139-144. ISSN: 0214-8358
papillae present on chaetigers 6 and 7; inserted intersegmentally, dorsal to notopodia (Fig. 2A).
Seventeen pairs of notopodia from segment 4.
Notochaetae of 2 lengths, all broad-bladed, narrowwinged capillaries (Fig. 3E, F, 4C). Neuropodia
from segment 5 (chaetiger 2) initially with uncini
arranged in single rows, subsequently uncini in double rows from seventh uncinigerous segment to last
thoracic segment; uncini arranged in single rows on
abdominal tori. Uncini from anterior uncinigerous
segments with well-chitinised long-handled shafts
and strongly crested heads with a dental formula
MF:5-6,5-6,6,7-?-?(Fig. 3G-K). Uncinal shafts pres-
NEW SPECIES OF PISTA (TEREBELLIDAE) FROM JAPAN • 143
FIG. 4. – SEM photo of Pista shizugawaensis n. sp. A, lateral view of anterior part of worm, showing tentacles and branchiae. B, branchiae. C,
7th thoracic chaetiger with chaetae. D, middle segment (6th chaetiger) uncini with long handles. E, posterior segment (16th chaetiger) uncini with
very short handle or lacking handle. F, abdominal uncini. Scale 1 mm in A, 0.5 mm in B, 50 μm in C, 25 μm in D and E, 15 μm in F.
TABLE 1. – Distribution and arrangement of branchiae in Pista shizugawaensis n. sp. Branchiae lacking (-) and 4 developmental states
(undeveloped, small, middle and large) are shown.
specimen
type
left
CMNH-ZW01800
SMF-15178
HNM-2005.1516
USNM-1078490
SAM-E3457
AMS-W.29405
ZMUC-POL-1851
LACM-AHF-Poly2170
Holotype
Paratype
Paratype
Paratype
Paratype
Paratype
Paratype
Paratype
2nd segment
right
large
large
middle
middle
large
undev.
small
large
ent on anterior and middle thoracic chaetigers (Figs.
3G, H, 4D) but those of posterior thoracic segments
are very short or lacking (Figs. 3I, J, 4E). Abdominal
uncini avicular without shaft, smaller than thoracic
ones (Figs. 3L, 4F).
Tube soft with incorporated sandy mud and shell
fragments, usually attached to underside of a large
stone or to rigid algal holdfasts, such as of Eisenia
bicyclis.
Variation. Branchial size is not constant even
within an individual; some branchiae lack developed
large
middle
undev.
large
middle
-
left
3rd segment
right
small
middle
large
undev.
large
middle
middle
large
middle
small
large
middle
middle
small
middle
undev.
remark
Fig. 2
Fig. 3
filaments and some are fully developed. In Table 1,
we tentatively separated the branchiae according to
size and development into 4 categories, I - undeveloped (0.6-1 mm length, without filaments; Fig. 3A
left), II - small (1-1.5 mm length, filaments are small
and not developed; Fig. 3B right, C and D), III - middle (stalk 2-3 mm long and branched dichotomously;
Fig. 3B left), IV - large (stalk long, 3-4 mm long, filaments long; Fig. 3A right). The number of pairs of
branchiae is a diagnostic character of the species but
the size and developmental states are not useful for
identification, as shown in Table 1. We suspect that
SCI. MAR., 70S3, December 2006, 139-144. ISSN: 0214-8358
144 • E. NISHI and K. TANAKA
they are capable of regenerating branchiae if lost by
predation.
these characters unfortunately have not been recorded in all Pista species making it impossible to complete a comparison with all species.
Etymology. The specific name refers to the type
locality, Shizugawa Bay, Sanriku Coast, Japan.
ACKNOWLEDGEMENT
Remarks. Pista shizugawaensis n. sp. can be distinguished from other species of the genus Pista by
the presence of lateral lobes on chaetigers 5 and 6.
While these lobes are small, they are clearly present
on type material, thus it is unlikely that they have
been missed in previous studies. Pista shizugawaensis n. sp also differs from other species of Pista
described from Japan (Imajima and Hartman, 1964)
and South China Sea (Hutchings, 1990)in the number and shape of branchiae, arrangement of the lateral lobes, arrangement of the nephridial papillae,
dental formula and development of the shaft in anterior thoracic uncini.
In Australian waters, where the family
Terebellidae has been well studied, 10 species of
Pista have been reported (Hutchings and Glasby,
1988). Comparing these taxa with P. shizugawaensis n. sp., the new species resembles P. australis, P.
sinusa, and P. curtiuncata in the number and shape
of branchiae. But P. shizugawaensis can be distinguished from them by the morphology and arrangement of lateral lobes on segments 2-4. In the dental
formula and shaft shape of uncini, P. shizugawaensis is similar to P. australis Hutchings and Glasby,
1988 and P. sinusa Hutchings and Glasby, 1988 but
SCI. MAR., 70S3, December 2006, 139-144. ISSN: 0214-8358
We acknowledge the staff of Shizugawa Nature
Centrefor their help in sampling and encouragement, and Dr. Pat Hutchings and anonymous referees for their useful comments on the ms. The work
is funded by Kanagawa Academy of Science and
Technology (KAST).
REFERENCES
Hutchings, P.A. – 1977. Terebelliform Polychaeta of the families
Ampharetidae, Terebellidae and Trichobranchidae from
Australia, chiefly from Moreton Bay, Queensland. Rec.
Australian Mus., 31: 1-38.
Hutchings, P.A. – 1990. Terebellidae (Polychaeta)from the Hong
Kong region. In: B. Morton (ed.), Proceedings of the Second
International Marine Biological Workshop: The Marine Flora
and Fauna of Hong Kong and Southern China, Hong Kong,
1986. Hong Kong University Press, Hong Kong.
Hutchings, P.A. and C.J. Glasby. – 1988. The Amphitritinae
(Polychaeta: Terebellidae) from Australia. Rec. Australian
Mus., 40: 1-60.
Imajima, M. and O. Hartman. – 1964. Polychaetous Annelids of
Japan. Occasional paper, Allan Hancock Foundation
Publications, No. 26, part II, 239-452. University of Southern
California Press, Los Angeles, California.
Uchida, H. – 1992. Polychaeta. In: S. Nishimura (ed.),
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Received September 15, 2004. Accepted May 11, 2005.